1. The commission may grant individual variances beyond the limitations prescribed in this chapter whenever it is found, upon presentation of adequate proof, that compliance with any provision of this chapter or any rule, requirement or order of the commission or director will result in a taking of property without just compensation or in the closing and elimination of any lawful business, occupation or activity, without sufficient corresponding benefit or advantage to the people; except, that no variance shall be granted where the effect of the variance will permit the continuance of a health hazard; and except, also, that any variance so granted shall not be so construed as to relieve the person who receives the variance from any liability imposed by other law for the commission or maintenance of a nuisance.

2. In determining under what conditions and to what extent a variance may be granted, the commission shall exercise a wide discretion in weighing the equities involved and the advantages and disadvantages to the applicant and to those affected by air contaminants emitted by the applicant.

3. Variances shall be granted for such period of time and under such terms and conditions as shall be specified by the commission in its order. The variance may be extended by affirmative action of the commission.

4. Any person seeking a variance shall do so by filing a petition for variance with the director. The director shall promptly investigate the petition and make a recommendation to the commission as to the disposition thereof. Upon receiving the recommendation of the director, if the recommendation is against the granting of a variance, a hearing shall be held if requested as provided in section 643.100. If the recommendation of the director is for the granting of a variance, the commission may do so without a hearing; except, that upon the petition of any person aggrieved by the granting of the variance, a hearing shall be held as provided in section 643.100. In any hearing under this section, however, the burden of proof shall be on the person petitioning for a variance.

5. Upon failure to comply with the terms and conditions of any variance as specified by the commission, the variance may be revoked or modified by the commission after a hearing held upon not less than thirty days’ written notice. The notice shall be served upon all persons who will be subjected to greater restrictions if the variance is revoked or modified and all persons who have filed with the director a written request for notification.

6. The director shall take action within thirty days after a petition has been filed and shall make a recommendation to grant or deny the petition for a variance within one hundred twenty days. If the director fails to make a recommendation within the time period specified, the person seeking the variance may request a hearing as provided in section 643.100.